Nonspillable vent plug



1935- J. 1.. WOODBRIDGE NONSPILLABLE VENT PLUG Filed Nov. 21, 1930 awn foe (Z e /z' 1 5/8) /Va0n 6r/a7 e IWT/YESS:

Patented Feb. 19, 1935 .NONSPILLABLE VENT PLUG Joseph Lester Woodbridge, Philadelphia, Pa., as-

signor to The Electric Storage Battery Company, Philadelphia, Pa., a. corporation of New Jersey Application November 21, 1930, Serial No. 497,157

4 Claims. (01.136-178) This invention relates to storage batteries and particularly to vent plugs therefor, and its object is to provide a vent plug for the cell of a storage battery, which will prevent the escape of electrolyte when the cell is turned over but will permit the escape of gases developed in the cell when the cell is in its normal upright position. To accomplish this result, a valve is provided in the vent plug, which is closed by the displacement of a heavy element which displacement occurs when the cell is tipped to a certain angle from the vertical and is opened when the heavy element is restored to its original position upon the restoration of the cell to its normal vertical position..

My invention will be more fully understood by reference to the accompanying drawing which shows in vertical section the upper part of a storage battery cell equipped with a vent plug embodying features of my invention.

In the drawing,

1 represents the upper part of the vertical walls of the storage cell containing electrolyte 2 and fitted with a cover 3 sealed to the cell walls by sealing compound 4111 the usual manner. The cover is provided with an internally threaded vent opening 5, into which is. fitted the lower threaded portion of the vent plug 6. This vent plug is provided below with an opening 7, which may be closed by a. hemispherical valve 8 when this is drawn upward against the spherical surface of thevalve seat 9. The valve 8 is suspended by means of the eye-bolt 10 and a similar eye-bolt 11 from the conical shaped heavy actuating element 12. The element 12 is in the form of a truncated cone with a downwardly extending skirt 13 resting on the internal ledge14 at the bottom of the-upper portion or barrel 15 of the vent plug 6. Openings 16 are shown through the skirt of the conical weight 12 to permit the.

escape of gases from the cell and to allow any liquid which may escape from the cell into the interior of the barrel 15 to drain back into the cell. When the conical weight 12 is in its normal position, resting on the ledge 14, the valve 8 will' point of contact 19 between the upper eye-bolt 11 and the lower eye-bolt 10 will also rotate about the point 18 and will therefore travel in a nearly axial direction upward, pulling the valve 8 into contact with its seat 9. The design should 5 be such that this contact will be efiected before the conical weight 12 rests against the inner wall of the barrel 15, so that its weight will be effective in holding the valve 8 in the closed position. When the vertical position of the cell is restored, the conical weight 12 will drop back into its original position, resting on the flange 14 and the valve 8 will be released and will drop back into the position shown in the drawing.

its weight as great as possible. The valve 8 also be made of acid resisting material.

weight 12 of lead antimony alloy and the valve -A cap 20 is provided for the top of the barrel 1 15, which may be attached to the latter in any suitable manner as by the threaded 'fiange 21. This cap has a depending vent tube 22 provided with lateral vent openings 23 and a lower terminal vent opening 24. Should a small amount of liquid escape from the cell into the barrel 15, this will be retained in the annular space 25 around thevent tube 22 when the cell is in the inverted position and will not escape from the vent plug but will be returned to the cell when the cell is restored to its normal position.

In carrying out my invention, it is preferable to so design the parts that the center ofgravity of the conical weight 12 is as high as possible and The parts should I have therefore found it preferable to make'the conical should be as light as possible.

8 of hard rubber.

It is also desirable that the point of contact 19 between the two eye-bolts be located about as far below the plane of the shoulder 14 when the conicalweight 12 is in its normal position as it is above said plane when the conical weight is in its tilted position, thus causing the travel of this contact point 19 to be as nearly as possible in an axial line.

It will be noted that the automatic action of this vent plug in closing and opening the valve, is independent of the direction in which the cell may be tipped. Also, the linking of the two eyebolts constitutes a universal joint, permitting an axial pull to be applied to the valve, notwithstanding the varying angular relation between the two eye-bolts.

The shape of the weight 12 need not necessarily beconical provided there is suificient clearance between this weight and the interior .walls of the barrel 15 to permit the weight to tilt through the desired angle.

I claim:

1-. A vent plug having walls defining a hollow chamber provided with upper and lower vent openings, a depending projection extending into said'hollow chamber and into said upper vent opening, a ledge extending into said lower vent opening, a frusto-conical actuating member having a perforated flangeforming its largest lateral dimension and forming its lowersurface and being located in said chamber and resting on said ledge in the normalposition of the plug but adapted to rotate about a point of contactwith the ledge upon tilting the plug, a valve member attached to .said actuating-member and adaptedto be moved by said actuating member to close the lower vent opening when in tilted position, and elements attached to said actuating member and to said valve member and having annular portions in engagement with each other to form a universal joint lying approximately in the plane of said ledge.

2. A vent plug having walls defining a hollow chamber provided with upper and lower vent openings, a depending projection extending into said hollow chamber and into said upper vent opening, a ledge presenting a substantially horizontal surface extending into said lower vent opening and extending to the lateral wall of the chamber, a frusto-conical actuating member having a depending flange forming its largest lateral dimension at its lower surface and being located in said chamber and resting on said ledge in the normal position of the plug but adapted to rotate about a point of contact with the ledge adjacent the lateral wall of the chamber upon tilting the plug, a valvemember attached to said actuating member and adapted to be moved by said actuating member to close the lower vent opening when the plug is in tilted position, and elements atmember having a peripheral projection restingon the ledge at and adjacent the walls of said space and adapted to rock about a point of contact betweenthe projection and the ledge at the walls of said space upon tilting of the vessel in any direction, and a single universal joint be-' tween the valve-actuating member and the valve member, the location of said universal joint being such that its travel consequent on the rocking.

oi the valve-actuating member to close said vent orifice will be substantially 'axial and substantially equal above and below the plane of the ledge. e

4. A vent plug for storage batteries comprising, a hollow chamber having openings adjacent its upper and lower ends, a support adjacent the lateral walls of said chamber, a valve-actuating member having various lateral dimensions and having its largest lateral dimension located on said support and extending substantially to the lateral walls of said chamber, a valve seat surrounding one of said openings, a valve co-'operating with said valve seat to close off communication through said chamber, and connections between said' valve-actuating member and said valve, said connections having a single universal joint therein located 'so that the median point in its path of movement is at the horizontal level of said support;

- JOSEPH LESTER WOODBRIDGE. 

